Jet steering boat

ABSTRACT

A boat has a plurality of water-jet nozzles mounted at the bow and stern to assist in steering the boat especially when docking. The water-jet nozzles also provide auxiliary drive to propel the boat at slow speeds. A pump supplies water to the water-jet nozzles, and a control mechanism operates the valves to move the boat forward, aft, sideways, and to rotate it clockwise and counterclockwise.

United States Patent Glass 51 July 1 l, 1972 JET STEERING BOAT 2,330,674 9/1943 Briggs ..114/151 [72} Inventor: John P. Glam, c/o Cava Industries 79 La Primary Examiner Trygve M mix Grange Ave, Esslngton. Pa. 19029 Arwmey john A Barley [22] Filed: Feb. 27, I970 [57] ABSTRACT [21] Appl. No.: 14,985

A boat has a plurality of water-jet nozzles mounted at the bow and stern to assist in steering the boat especially when [52] US. Cl. ..ll5/l2 R, l l4/l5l docking The waer jet nozzles also provide ifi drive to Int. propel the boat at slow speed5 A pump upplies water to [he Field sul'ch 4. l l. 16; l l4/ water-jet nozzles. and a control mechanism operates the /22! valves to move the boat forward. aft, sideways. and to rotate it clockwise and counterclockwise. [56] References Cited 13 Claims, 9 Drawing figures UNITED STATES PATENTS 3,132,477 5/[964 Egger ..llS/IZX PMENTEDJUL 1 z 1572 SHEET 1 0F 2 F I G. 3.

F l G. 4.

F I G. 2.

INVENTOR JOHN P. GLASS ATTORfi PKTENTEDJHL 1 1 I972 SHEET 2 OF 2 F l G. 5.

LL s3 s4 F l G. 7.

F I G. 9.

F l G. 8.

INVENTOR JOHN P. GLASS gLLfdcihv ATTORNEY JET STEERING son BACKGROUND OF THE INVENTION Twin engine boats are generally preferred over single engine boats by amateur boatsmen because they hesitate to rely on a single engine when the boat is far out at sea. However, commercial lobster boats and trawlers which operate far at sea are generally single engine boats. A big hazard in boats is the outside gear which may strike objects that will damage it. A single screw can be tucked under a skate, the extended portion of the keel, with the boat hull extending to the side a sufficient distance so that the screw is well protected against being struck by sand bars, rocks or other articles that would cause damage. Accordingly, the single screw boat is more reliable than the twin screw boat because it is less vulnerable to outside damage.

A boat is also subject to inboard troubles such as engine failure, but engine troubles on a boat are usually minor, and since the engines are inboard, they are accessible for making repairs.

Another reason that prevents popular acceptance of the single screw boat is that it is more difficult to steer and dock. A twin screw boat may be steered in the same way as a tank, e.g. one engine may be reversed or stopped entirely and the other engine may go full forward to turn the boat around in its own length. But a single screw boat is not as easy to steer, especially at the low speeds involved in docking.

Some rather large ships which call at ports in South America that do not have tug boats have a steering device called a side-thruster mounted on the bow. The side-thruster is an airplane propeller mounted so that its plane of rotation is parallel to the keel of the ship. In operation, with the stern of the ship still tied to the wharf, the side-thruster is turned on to swing the bow into the channel. When the bow is pointed in the proper direction, the stern lines are cast off, and the screw propels the boat forwardly in the water. However, the sidethruster is large and rather complex mechanically, is relatively inflexible, and is not adapted for use by small boats.

SUMMARY OF THE INVENTION Accordingly, it is an object of this invention to provide a boat which is more easily steered and docked at slow speeds.

It is another object to provide a boat with an auxiliary drive which may be operated instead of the screw.

It is another object to provide an auxiliary drive having sufficient momentum to move the boat by moving a relatively large mass of water at a substantial velocity, said auxiliary drive including relatively uncomplicated mechanisms.

The objects of the invention are accomplished by providing: water-jet nozzles at the bow and stem of the boat, a pump which supplies water to the nozzles, valves connected to the nozzles, and control means for selectively turning the valves on and oil.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a top plan view of a jet-steering boat constructed in accordance with the invention;

FIG. 2 is a schematic view of the boat of FIG. 1 illustrating the directions of the water jets;

FIG. 3 is a perspective view of a pilot valve in accordance with the invention;

FIG. 4 is a horizontal section of the pilot valve of FIG. 3;

FIG. 5 is a horizontal section of a first alternative pilot valve;

FIG. 6 is a horizontal section of a second horizontal pilot valve;

FIG. 7 is a horizontal section of a third alternative pilot valve;

FIG. 8 is a vertical section of a control valve for delivering water to a nozzle; and

FIG. 9 is a vertical section of the control valve of FIG. 6 taken on the surface 9-9 indicated in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a boat [0 having a bow end 12 and a stem end 14. A keel line I6 extends between the bow and the stern.

At the stern, water jet nozzles are provided at 25, 26, 27 and 28. Ports l8 and 20 are provided on opposite sides of the bow. Port 18 provides an opening for a pair of nozzles 21 and 22, and port 20 provides an opening for a pair of nozzles 23 and 24. Arrows in FIG. 2 illustrate the directions of the nozzles. With respect to the keel line, nozzles 21 through 28 are respectively pointed in the directions 330, 300, 60, 30, I20", 150, 210", and 240. The directions of the water jets, then, are in four quadrants, two jets being provided for each quadrant. The two jets in each quadrant are pointed in different directions, and both directions are oblique with respect to the keel line 16. It will be observed that, although there are four pairs of opposite jet directions, e.g. 60, 240, the jets in a pair of opposite jets are not aligned with each other. The reason for the non-alignment is to produce a force couple in order to rotate the boat. The exact directions are not critical, but it is important that the oppositely directed jets be out of alignment with each other.

An engine 30 is mounted in the boat, and is connected to drive a screw 32 through a shaft 34 which is aligned with the keel line 16. A clutch is provided at 36 for disconnecting the screw from the engine output shaft. A centrifical hydraulic pump 38 is connected to the shaft of engine 30 by a clutch 40. Pump 38 takes in sea water through an intake line 39 and delivers it under pressure through line 42 to a line 44, through which it is delivered to valve assembly 46 in the bow and to valve assembly 48 near the stern. A portion of the output of the pump is delivered through line 50 to a pilot valve assembly 52 for control purposes.

Lines 61, 62, 63 and 64 are connected between the pilot valve and the forward valve assembly 46. Lines 65, 66, 67 and 68 are connected between pilot valve 52 and the stern Valve assembly 48. It should be noted at this point that one control line is provided for each of the water jet nozzles, and that the second digits of the reference numerals for the control lines and the nozzles correspond.

Valve assembly 46 consists of four pressure controlled valves 71, 72, 73 and 74, these being associated respectively with nozzles 21, 22, 23 and 24 to control the flow of water from line 44 to the respective nozzles. Valves 7I-74 are controlled respectively through control lines 61-64.

At the stern, valve assembly 48 comprises valves 75, 76, 77 and 78. These valves are associated respectively with nozzles 25, 26, 27 and 28 to control the flow of water from line 44 through the nozzles. The valves are controlled respectively through lines 65, 66, 67 and 68.

The valves just described are identical. FIG. 8 shows valve 71 in vertical section. A manifold 80 receives water from line 44, and a diaphragm 81 is arranged to control the flow of water from manifold 80 to nozzle 2I depending on the relationship between the pressure in chamber 82 above the diaphragm and the presure below the diaphram. Chamber 82 is connected to control line 61, and a spring 83 within chamber 82 normally urges the diaphragm downwardly against seat 84. It will be apparent, that so long as a pressure is maintained in line 61, which is equal to or greater than the pressure in manifold 80, diaphragm 81 will remain closed against seat 84 and no flow will take place through nozzle 2!. If anY flow tends to take place between the diaphragm and nozzle, the decrease in pressure will force the diaphragm in a closing direction. Spring 83 is not necessary to insure closing of the control valve, but provides a safety margin.

Whenever line 61 is opened to the atmosphere, the water pressure in manifold 80 will cause the diaphragm to open, and water will flow through the nozzle to exert a thrust on the boat in the direction opposite to the direction of flow through the nozzle. Several pilot valves will now be described which are capable of selectively opening the control lines 61-68 to the atmosphere in order to activate combinations of nozzles for maneuvering the boat. FIG. 3 shows a tank 85 in the form of a closed cylinder having an opening 86 in its underside through which line 50 delivers water under pressure from the pump outlet line 42. A central opening 87 on the underside of the tank is open to the atmosphere through line 88. The eight control lines 61-68 are in communication with the interior of tank 85 through various openings provided on the underside of the tank. The positions of these openings will depend on the configuration of the particular control valve which will be located within the tank and controlled through rod 89 which extends through a seal 90 on the upperside of tank 85. A control knob 91 may be boat-shaped so that it indicates the direction of movement of the boat. The lower end of the rod 89 is connected to the control valve 92 through a universal joint 94.

Control valve 92 may take various forms. The first form is illustrated in FIG. 4 which is a horizontal section through the tank 85. Openings 101-108 are provided in the bottom of the tank in the positions shown, and are connected respectively to control lines 61-68. Valve member 110 has a closed top, and is enclosed by vertical sides 112 and 113. Its ends are enclosed by vertical elements 114, which are oblique to sides 112 and 113, and by vertical elements 1 16, which are perpendicular to sides 112 and 113. Rectangular elements 118 complete the vertical enclosure. Valve member 110 is open at its bottom, and its lower edges cooperate with the lower plate 120 of the tank to provide a water-tight closure within the tank and on the outside of the valve. The interior of the valve member 110 is in continuous communication with the atmosphere through opening 87. With the valve member in the position shown, the interior of the tank outside the valve member forms part of a system pressurized through opening 86. Each of the eight control lines is in communication with line 86 through the tank. The pressure within the tank holds the valve member in tight engagement with the bottom plate 120 of the tank.

In the case of FIG. 4, a reversing gear is provided at the location of seal 90 so that valve member 110 rotates in the direction opposite to the direction of rotation of control knob 91. If control knob 91 is rotated one step clockwise, valve member 110 rotates to the left until elements 118 cover openings 101 and 106. Lines 61 and 66 are then in communication with the atmosphere through the interior of valve member 110, and controlled valves 71 and 76 (FIG. 1) are opened activating nozzles 21 and 26. The activation of nozzles 21 and 26 effects a slow clockwise rotation of the boat.

lf control knob 91 is rotated further in a clockwise direction, openings 102 and 105 are covered by elements 118 of the valve member, and nozzles 22 and 25 are activated imparting a more rapid clockwise rotation to the boat since nozzles 22 and 25 are further out of alignment with each other than are nozzles 21 and 26. It will be noted at this point that whenever openings are uncovered by the valve member, their associated lines are again pressurized by the pressure within tank 85. Counterclockwise rotation of the control knob will effect counterclockwise rotation of the boat in a similar manner.

Assuming that the valve member 110 is returned to the position shown, a rearward movement of control knob 91 will ef' feet a forward movement of valve member 110, seal 90 acting as a pivot. Openings 101 and 104 are now covered, and nozzles 21 and 24 are activated to impart a rearward movement to the boat. A forward movement of the control knob similarly effects a forward movement of the boat by covering openings 106 and 107 thereby activating nozzles 26 and 27.

The control knob 41 can also be moved to the right, causing valve member 110 to cover openings 102 and 108. Nozzles 22 and 28 are then activated causing the boat to move sideways toward the starboard. Movement to the port can be effected similarly by moving control knob 91 toward the left to cause member 110 to cover openings 103 and 105 to activate nozzles 23 and 25.

FIG. illustrates an alternative embodiment of the invention in which the bottom plate 122 of a tank 124 is provided with an inlet opening 126 for delivering water from the pump into the interior of the tank, and a plurality of openings for connection to control lines 61-68. Openings 131 and 141 are connected to control line 61. Openings 132 and 142 are connected to control line 62. Openings 133 and 143 are connected to control line 63. Openings 134 and 144 are connected to control line 64. Openings 135 and are connected to control line 65. Openings 136 and 146 are connected to control line 66. Openings 137 and 147 are con' nected to control line 67. Openings 138 and 148 are connected to control line 68. Openings 131-138 form an outer ring for rotation control, while openings 141 through 148 are provided for controlling forward, rearward and sideways movement.

An outlet 150 communicating with the atmosphere is covered by a valve member 152 which is similar to valve member 110 shown in FIG. 4. The valve member has oblique comers 154, and rectangular extensions 156 and 158 which extend beyond the outer ring of openings.

Movement of valve member 152 by its control rod effects control of the boat in the same manner as movement of valve member 110 (FIG. 4). Openings 131-138 are covered in pairs by projections 156 and 158 when the valve member is rotated to effect rotation of the boat. For example, counterclockwise rotation of the control rod will cause valve member 152 to rotate counterclockwise (there being no reversing gear) and projections 156 and 158 will first cover openings 134 and 137 respectively. The pressure in lines 64 and 67 is then relieved, and nozzles 24 and 27 are activated to cause the boat to rotate slowly toward the left.

If the valve member is moved forwardly, rearwardly, or to either side, a pair of openings of the group of openings 141-148 will be covered by the valve member. For example, if the control knob is moved toward the right, valve member 152 will be moved to the left, covering openings 142 and 148. The pressure in lines 62 and 68 will then be relieved, and nozzles 22 and 28 will be activated causing the boat to move sideways toward the starboard.

FIG. 6 illustrates an embodiment of the pilot valve in which the pressurized tank 160 is provided with eight openings 161-168 in its bottom plate 169. Openings 161-168 are in communication respectively with control lines 61-68. An opening delivers water under pressure into the interior of the tank from line 50.

As best seen in FlG. 9, a plate 172 is provided, which in its normal position covers all of the openings in the bottom 169 of the tank. An annular ring 174 depends from plate 172 to define in part, an enclosure 176 which is filled with water through line 50. The portion of the tank outside enclosure 176 is in communication with the atmosphere through pipe 178. Plate 172 is movable in all horizontal directions and rotatable by control rod 180 which extends into a reversing gear box 182 which is pivoted for universal movement in pivot 184. A universaljoint 186 fastens rod 188 to the top of plate 172, rod 188 being coupled to the gearing in gear box 182.

Various elongated and circular openings are provided in plate 172, the circular openings being provided to permit rotational movement of the boat, and the elongated openings being provided for forward, rearward and sideways movement. Each of the holes in the plate is provided with a boss which extends downwardly to the bottom of the tank to complete enclosure 176 and to prevent the escape of water from enclosure 176 into the part of the tank located above the plate. Elongated opening 191, for example, is provided with a depending boss 201 (see FIG. 9).

All of the lines 61-68 are in communication with line 50 through enclosure 176, and are thereby pressurized when plate 172 is in its neutral position as shown in FIGS. 6 and 9. However, if the plate is moved to a position in which its opening in the plate is aligned with an opening in the bottom of the tank, the pressure in that line will be relieved since it is opened to atmospheric pressure within the tank above plate 172. If shaft 180 is rotated in a clockwise direction, shaft 188 will cause plate 172 to rotate in a counterclockwise direction so that opening 211 comes into alignment with opening 161 and opening 216 comes into alignment with opening 166. The pressure in lines 61 and 66 is then relieved, and nozzles 21 and 26 will be activated to cause the boat to rotate in a clockwise direction. There is no provision in the embodiment illustrated in FIGS. 6 and 9 for a second step to cause the boat to rotate more rapidly. 1f the control knob is moved rearwardly, plate 172 moves forwardly and elongated openings 221 and 224 are moved into alignment with openings 161 and 164 respectively. The pressure in lines 61 and 64 is relieved and nozzles 21 and 24 are activated, moving the boat rearwardly. The remaining openings in plate 172 permit the selective relief of pressure in the various lines of group 61-68 to effect movements of the boat in different directions.

In FIG. 7, there is illustrated a tank 230 having an inlet opening 231 to be connected to the outlet of pump 38. A plate 232, similar to the plate illustrated in FIG. 9 except for the configuration of its openings rests on the bottom 234 and is controlled by a control rod 236 through a universal joint 238. in this embodiment, the control rod is not provided with a reversing gear. The bottom 234 of the tank is provided with openings 241-248 which are respectively in communication with lines 61-68. The bottom of the tank is provided with eight additional openings 251-258, which are also in communication with the respective lines 61-68. The plate 232 is provided with openings 262 and 264 near its periphery at a radius from its center which is equal to the distance from the center of the tank bottom to any one of openings 241-248. Openings 262 and 264 are provided with depending bosses similar to those illustrated in FIG. 9 to prevent communication between the space above the plate and the pressurized space below it. The plate is further provided with elongated openings 271-278, these openings also being provided with depending bosses.

Rotation of the plate will cause the pressure in pairs of lines to be relieved by the opening of the lines to the atmospheric pressure above the plate through openings 262 and 264 in the plate. For example, rotation of the control knob one step counterclockwise will cause the plate to rotate counter clockwise aligning opening 262 with opening 244 and aligning opening 264 with opening 247. Lines 64 and 67 are thereby relieved, and nozzles 24 and 27 are activated causing the boat to rotate counterclockwise slowly. If the knob is rotated further to the left, lines 64 and 67 are again pressurized by the liquid in the space underneath the plate, and lines 63 and 68 are relieved through openings 262 and 264 respectively. Nozzlcs 23 and 28 are then activated to cause a more rapid counterclockwise rotation of the boat. Clockwise movement of the boat is accomplished in a similar manner by clockwise rotation of the control knob.

1f the control knob is moved forwardly, opening 277 is moved into alignment with opening 257, and opening 276 is moved into alignment with opening 256. Lines 67 and 66 are relieved, and nozzles 27 and 26 are activated to move the boat forwardly. Rearward and sideways movement of the boat are accomplished in a similar manner by a rearward and sideways movement of the control knob in the desired directions.

The centrifical hydraulic pump 38 if preferably adapted to use about to of the engine horsepower, and may be disconnected from the engine 30 by disengagement of clutch 40 when the water-jet nozzles are not being used in order not to waste power.

Flaps may be provided on the forward openings 18 and 20 in order to avoid taking in sticks, stones and other foreign matter.

The jet-steering apparatus of the present invention is especially adapted for use in docking, but it may also be used as an auxiliary drive to propel the boat at a speed ofa few knots instead of the main screw. This apparatus is adapted for use even in twin screw boats, and is useful in moving such a boat in shallow water instead of using the screws, thereby avoiding the danger of the revolving screws striking anything that would cause damage.

Various modifications may be made to the invention. For example, the control system can use a pneumatic medium rather than hydraulic. As a further alternative, electrical control of the controlled valves 71-77 is possible.

1 claim:

1. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of waterjet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, valve means for controlling the flow of said water under pressure through selected combinations of said nozzles, and manually positionable means for effecting control of said valve means, said manually positionable means activating a combination of nozzles for producing a net propulsive force on said boat when said manually positionable means is displaced from a neutral position, and activating a combination of nozzles to create a force couple of jets of water for turning said boat when said manually positionable means is rotated while remaining in said neutral position.

2. A boat according to claim 1 wherein a first bow nozzle and a second stern nozzle are arranged to direct water toward the right of said keel line and a second bow nozzle and a first stern nozzle are arranged to direct water toward the left of said keel line, said first nozzles being out of alignment and said second nozzles being out of alignment, and wherein said valve means includes means connected to and movable by said manually positionable means for activating said first nozzles when said manually positionable means is rotated in one direction to produce a force couple to rotate the boat in one direction, and for actuating said second nozzles when said manually positionable means is rotated in the opposite direction to produce a force couple to rotate the boat in the opposite direction.

3. A boat according to claim 1 wherein a first nozzle mounted in an end of said boat is arranged to direct water in an oblique direction forwardly and to the right with respect to the keel line, a second nozzle mounted in said one end of said boat is arranged to direct water in an oblique direction forwardly and to the left with respect to the keel line, a third nozzle mounted in the other end of said boat is arranged to direct water in an oblique direction rearwardly and to the right with respect to said keel line, and a fourth nozzle mounted in said other end of said boat is arranged to direct water in an oblique direction rearwardly and to the left with respect to said keel line, and wherein said manually positionable means has at least four positions: for activating said first and second nozzles when pushed to the first of said four positions, said third and fourth nozzles when pushed to the second of said positions, said first and fourth nozzles when rotated to the third of said positions, and said second and third nozzles when rotated to the fourth of said positions.

4. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of waterjet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, valve means for controlling the flow of said water under pressure through selected combinations of said nozzles, and manually positionable means for effecting control of said valve means, said manually positionable means activating a combination of nozzles for producing a net propulsive force an said boat when said manually positionable means is displaced from a neutral position, and activation a combination of nozzles to create a force couple of jets of water for turning said boat when said manually positionable means is rotated while remaining in said neutral position wherein a first nozzle mounted in an end of said boat is arranged to direct water in an oblique direction forwardly and to the right with respect to the keel line, a second nozzle mounted in said one end of said boat is arranged to direct water in an oblique direction forwardly and to the left with respect to the keel line, a third nozzle mounted in the other end of said boat is arranged to direct water in an oblique direction rearwardly and to the right with respect to said keel line, and a fourth nozzle mounted in said other end of said boat is arranged to direct water in an oblique direction rearwardly and to the left with respect to said keel line, and wherein said control means includes manually operable means having at least four positions: for activating said first and third nozzles when pushed to the first of said four positions, said second and fourth nozzles when pushed to the second of said positions, said first and fourth nozzles when rotated to the third of said positions, and said second and third nozzles when rotated to the fourth of said positions.

5. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of waterjet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, wherein said pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided in each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel liner 6. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of waterjet nozzles mounted in the how, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, wherein said pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided in each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel line, and wherein said control means includes manually operable means for activating selected pairs of said nozzles from a group of possible selected pairs.

7. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of waterjet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combina tions of said nozzles, said control means comprising a tank, means for pressurizing a fluid in said tank, a plurality of control lines communicating with the interior of said tank through openings in a wall, means slidable on said wall within said tank and cooperating with said wall to define a moveable, fluidtight space within said tank, an open conduit connecting said fluid-tight space to the atmosphere, said openings being arranged so that combinations thereof can be put in communication with the atmosphere when covered by said slidable means, and a plurality of controlled valves, each being associated with one of said nozzles to control the flow of water through said one of said nozzles, each said controlled valve being connected to be controlled by the pressure of fluid in one olsaid lines.

8, A boat according to claim 7 in which each said controlled valve comprises means defining a passage forming part of a conduit for delivering water to a nozzle, a valve seat within said passage, a moveable diaphragm adapted to cooperate with said valve seat to regulate the flow of water through said passage, and means defining a chamber on one side of said moveable diaphragm partially enclosed by said diaphragm and in communication with the associated one of said control lines so that the position of said diaphragm with respect to said seat is dependent on the pressure of the fluid in said one of said control lines.

9. A boat according to claim 7 in which the pump means for supplying water under pressure and the means for pressurizing a fluid in said tank are both constituted by a centrifugal hydraulic pump.

10. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controllin the flow of said water under pressure through selected com rnations of said nozzles, wherein sa|d pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided for each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel line and wherein said control means includes manually operable means having at least eight positions for activating pairs of nozzles, the nozzles in each of said pairs being in different quadrants, for directing water in adjacent directions in the first four of said positions and for actuating pairs of nozzles for directing water in the most nearly opposite directions in another four of said eight positions, the nozzles in the last-mentioned pairs being arranged out of line with each other so that the water jets delivered by said nozzles produce a couple tending to turn the boat.

II. A boat according to claim 10 in which said eight nozzles are arranged to direct water jets at 30, 60, l20, I50, 2 l0", 240, 300, and 330 with respect to the keel line.

12. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stem, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, said control means comprising a surface having a plurality of openings extending through it, a plurality of control lines on one side of said surface communicating with said openings, an additional opening in said surface, means on said one side of said surface delivering a fluid under pressure to said additional opening, means slidable on the opposite side of said surface and cooperating with said surface to define an enclosure, said enclosure being normally in communication with all of said control lines and said means delivering a fluid under pressure, said means cooperating with said surface including projections having passages extending through their interiors for providing communication between a control line and the atmosphere when one of said passages is aligned with an opening communicating with said control line, and a plurality of controlled valves, each being associated with one of said nozzles to control the flow of water through said one of said nozzles, each said controlled valve being connected to be controlled by the pressure of fluid in one of said lines.

13. A boat according to claim 12 is which each of said controlled valves comprises means defining a passage forming part of a conduit for delivering water to a nozzle, a valve seat within said passage, a moveable diaphragm adapted to cooperate with said valve seat to regulate the flow of water through said passage and means defining a chamber on one side of said moveable diaphragm partially enclosed by said diaphragm and in communication with the associated one of said control lines so that the position of said diaphragm with respect to said seat is dependent on the pressure of the fluid in said one of said control lines.

i l =0 l I 

1. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of waterjet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, valve means for controlling the flow of said water under pressure through selected combinations of said nozzles, and manually positionable means for effecting control of said valve means, said manually positionable means activating a combination of nozzles for producing a net propulsive force on said boat when said manually positionable means is displaced from a neutral position, and activating a combination of nozzles to create a force couple of jets of water for turning said boat when said manually positionable means is rotated while remaining in said neutral position.
 2. A boat according to claim 1 wherein a first bow nozzle and a second stern nozzle are arranged to direct water toward the right of said keel line and a second bow nozzle and a first stern nozzle are arranged to direct water toward the left of said keel line, said first nozzles being out of alignment and said second nozzles being out of alignment, and wherein said valve means includes means connected to and movable by said manually positionable means for activating said first nozzles when said manually positionable means is rotated in one direction to produce a force couple to rotate the boat in one direction, and for actuating said second nozzles when said manually positionable means is rotated in the opposite direction to produce a force couple to rotate the boat in the opposite direction.
 3. A boat according to claim 1 wherein a first nozzle mounted in an end of said boat is arranged to direct water in an oblique direction forwardly and to the right with respect to the keel line, a second nozzle mounted in said one end of said boat is arranged to direct water in an oblique direction forwardly and to the left with respect to the keel line, a third nozzle mounted in the other end of said boat is arranged to direct water in an oblique direction rearwardly and to the right with respect to said keel line, and a fourth nozzle mounted in said other end of said boat is arranged to dIrect water in an oblique direction rearwardly and to the left with respect to said keel line, and wherein said manually positionable means has at least four positions: for activating said first and second nozzles when pushed to the first of said four positions, said third and fourth nozzles when pushed to the second of said positions, said first and fourth nozzles when rotated to the third of said positions, and said second and third nozzles when rotated to the fourth of said positions.
 4. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, valve means for controlling the flow of said water under pressure through selected combinations of said nozzles, and manually positionable means for effecting control of said valve means, said manually positionable means activating a combination of nozzles for producing a net propulsive force an said boat when said manually positionable means is displaced from a neutral position, and activation a combination of nozzles to create a force couple of jets of water for turning said boat when said manually positionable means is rotated while remaining in said neutral position wherein a first nozzle mounted in an end of said boat is arranged to direct water in an oblique direction forwardly and to the right with respect to the keel line, a second nozzle mounted in said one end of said boat is arranged to direct water in an oblique direction forwardly and to the left with respect to the keel line, a third nozzle mounted in the other end of said boat is arranged to direct water in an oblique direction rearwardly and to the right with respect to said keel line, and a fourth nozzle mounted in said other end of said boat is arranged to direct water in an oblique direction rearwardly and to the left with respect to said keel line, and wherein said control means includes manually operable means having at least four positions: for activating said first and third nozzles when pushed to the first of said four positions, said second and fourth nozzles when pushed to the second of said positions, said first and fourth nozzles when rotated to the third of said positions, and said second and third nozzles when rotated to the fourth of said positions.
 5. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, wherein said pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided in each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel line.
 6. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, wherein said pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided in each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel line, and wherein said control means includes manually operable means for activating selected pairs of said nozzles from a group of possible selected pairs.
 7. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzlEs mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, said control means comprising a tank, means for pressurizing a fluid in said tank, a plurality of control lines communicating with the interior of said tank through openings in a wall, means slidable on said wall within said tank and cooperating with said wall to define a moveable, fluid-tight space within said tank, an open conduit connecting said fluid-tight space to the atmosphere, said openings being arranged so that combinations thereof can be put in communication with the atmosphere when covered by said slidable means, and a plurality of controlled valves, each being associated with one of said nozzles to control the flow of water through said one of said nozzles, each said controlled valve being connected to be controlled by the pressure of fluid in one of said lines.
 8. A boat according to claim 7 in which each said controlled valve comprises means defining a passage forming part of a conduit for delivering water to a nozzle, a valve seat within said passage, a moveable diaphragm adapted to cooperate with said valve seat to regulate the flow of water through said passage, and means defining a chamber on one side of said moveable diaphragm partially enclosed by said diaphragm and in communication with the associated one of said control lines so that the position of said diaphragm with respect to said seat is dependent on the pressure of the fluid in said one of said control lines.
 9. A boat according to claim 7 in which the pump means for supplying water under pressure and the means for pressurizing a fluid in said tank are both constituted by a centrifugal hydraulic pump.
 10. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, wherein said pluralities of water-jet nozzles comprise at least eight nozzles, two of said nozzles being provided for each quadrant to direct water in two different directions in each quadrant, each direction being oblique with respect to the keel line and wherein said control means includes manually operable means having at least eight positions for activating pairs of nozzles, the nozzles in each of said pairs being in different quadrants, for directing water in adjacent directions in the first four of said positions and for actuating pairs of nozzles for directing water in the most nearly opposite directions in another four of said eight positions, the nozzles in the last-mentioned pairs being arranged out of line with each other so that the water jets delivered by said nozzles produce a couple tending to turn the boat.
 11. A boat according to claim 10 in which said eight nozzles are arranged to direct water jets at 30*, 60*, 120*, 150*, 210*, 240*, 300*, and 330* with respect to the keel line.
 12. A boat comprising a hull having a bow, a stern and a keel line extending between the bow and stern, a plurality of water-jet nozzles mounted in the bow, a plurality of water-jet nozzles mounted in the stern, pump means for supplying water under pressure to the nozzles, and control means for controlling the flow of said water under pressure through selected combinations of said nozzles, said control means comprising a surface having a plurality of openings extending through it, a plurality of control lines on one side of said surface communicating with said openings, an additional opening in said surface, means on said one side of said surface delivering a fluid under pressure to said additional opening, means slidable on the opposite side of said surface and cooperating with said surFace to define an enclosure, said enclosure being normally in communication with all of said control lines and said means delivering a fluid under pressure, said means cooperating with said surface including projections having passages extending through their interiors for providing communication between a control line and the atmosphere when one of said passages is aligned with an opening communicating with said control line, and a plurality of controlled valves, each being associated with one of said nozzles to control the flow of water through said one of said nozzles, each said controlled valve being connected to be controlled by the pressure of fluid in one of said lines.
 13. A boat according to claim 12 is which each of said controlled valves comprises means defining a passage forming part of a conduit for delivering water to a nozzle, a valve seat within said passage, a moveable diaphragm adapted to cooperate with said valve seat to regulate the flow of water through said passage and means defining a chamber on one side of said moveable diaphragm partially enclosed by said diaphragm and in communication with the associated one of said control lines so that the position of said diaphragm with respect to said seat is dependent on the pressure of the fluid in said one of said control lines. 